TIPSS术中胆汁漏出对内皮细胞NOS活性影响的研究

目的：探讨经颈静脉肝内门腔分流术（TIPSS）中胆汁漏出对内皮细胞一氧化氮合酶（NOS)及一氧化氮（NO）合成的影响,进一步了解胆汁对支架内皮化的影响。方法：取人脐静脉内皮细胞进行体外培养,加入不同浓度（5％、10％、15％、20％、25％）胆汁干预,观察内皮细胞生长状况,并测条件培养液中NO及细胞NOS活性。结果：含5％、10％、15％胆汁的细胞生长状况与不含胆汁者相似,含20％、25％胆汁的细胞明显减少并显幼稚;各浓度胆汁的细胞NOS活性较不含胆汁者明显降低;条件培养液中NO含量均无明显差异。结论：胆汁抑制内 皮细胞的生长,并抑制内皮细胞NOS活性。     

血清高迁移率蛋白-1水平变化与多发伤患者脏器功能不全及死亡率的关系

目的 研究多发伤患者伤后血清高迁移率蛋白-1（HMGB-1）的水平变化，以预测是否发生脏器功能不全（OD）及死亡率。方法测定35例多发伤患者伤后1，3，7d血清的HMGB-1，同时评定OD的发生情况和死亡率。了解HMGB-1水平变化及其与OD和死亡率的相关性并进行预测。结果（1）以是否发生OD分组，多发伤患者两组之间第1天和第3天HMGB—1值比较，差异有统计学意义（分别为t=4．411，P＜0．01，t=5．764，P＜0．01）。（2）以死亡或生存分组，多发伤患者两组之间第1，3，7天HMGB-1值比较差异无统计学意义。（3）创伤后第1，3天HMGB—1水平与OD明显相奖（P＜0．01）。（4）以是否发生OD分组，两组之间第1天HMGB-1值比较，差异有统计学意义（χ^2=17．850，P＜0．01）。第1天HMGB-1与正常者积分吸光度（A）比值≥1.08，OD发生率增加（χ^2=4．000，P＜0．05）。第1天HMGB-1与正常者积分吸光度比值≥1．35，OD发生率明显增加（χ^2=6．296，P＜0．05）。（5）以是否发生OD分组，两组之间第3天HMGB—1值比较，差异有统计学意义（χ^2=30．000，P＜0．01）。第3天HMGB—1与正常者积分吸光度比值≥1．35，OD发生率明显增加（χ^2=14．583，P＜0．01）。结论伤后第1、3天HMGB-1水平与OD发生率密切相关，可以预测创伤后OD发生，但对创伤后死亡或生存无预测作用。     

^131I对分化型甲状腺癌细胞核因子KB表达和功能的影响

目的探讨^131I对DTC细胞核因子KB（NF-KB）表达和功能的影响,以及^131I和NF-KB抑制剂Bay11-7082联合治疗的可行性。方法用不同放射性浓度^131I和不同浓度Bay11-7082处理DTC细胞,加入四氮唑盐显色,测定450nm的吸光度（A）值,用公式（A药物处理组-A空白）／（A对照组-A空白）×100％计算癌细胞存活率（A空白为空白孔的吸光度,A对照组为单纯细胞孔的吸光度）;选择癌细胞存活率约60％左右的^131I和Bay11-7082浓度进行联合实验。将^131I和Bay11-7082作用于DTC细胞6、24和48h后,提取核蛋白,分别与NF-KB结合序列探针相结合,测定450nm的A值,NF-KB的DNA结合率=（A药物处理组-A空白）／（A对照组-A空白）×100％。用Westernblot鉴定单用^131I、Bay11-7082和联合用药6h后NF-KB核蛋白相对表达水平的变化,并以B-actin作为内参对照进行半定量分析。用配对t检验、F检验和q检验进行统计分析。结果细胞存活分析发现不同放射性浓度^131I和不同浓度Bay11-7082处理后癌细胞的存活率不同（F=281．07和173．84,P均〈0．01）;单用^131I组、单用Bay11-7082组与联合用药组癌细胞的存活率分别为（67．33±5．65）％、（61．83±6．68）％和（36．67±5．35）％,差异有统计学意义（F=45．79,P〈0．01）,其中前2组分别与联合处理组相比q=8．20和8．35,P均〈0．01。DNA结合实验证实”。I可以诱导癌细胞内NF-KB结合率增高,24h为（255．33±29．86）％（最高）;而联合使用Bay11-7082后,在6、24和48h时间点能够抑制到相应刺激状态下NF-KB功能的22．10％、39．75％和43．18％,联合处理组与单用^131I组比较,3个时间点差异均有统计学意义（t：24．58、26．29和8．20,P均〈0．01）;6h时NF-KBp65功能受抑程度最明显,DNA结合率仅为（35．33±8．21）％,与对照组相比差异有统计学意义（t=28．98,P〈0．01）。半定量分析：^131I作用6h后p65和pSO相对表达水平均升高,Bay11-7082联合^131I作用6h后两者的表达水平均受到明显抑制;不同给药方式作用后p65和p50的相对表达水平差异均有统计学意义（F=100．93和193．55,P均〈0．01）,^131I组和对照组两两比较,q=4．75和8．22,P均〈0．05,联合处理组与对照组两两比较,q=30．80和22．83,P均〈0．01。结论^131I会导致DTC细胞NF-KB表达增加、功能增强,联合使用NF-（B抑制剂可以抑制这种改变,获得协同疗效。     

^99Tc^m—MIBISPECT结合定位CT显像诊断功能亢进异位甲状旁腺的价值

目的评价^99Tc^m-甲氧基异丁基异腈（MIBI）SPECT结合定位CT显像对功能亢进异位甲状旁腺的定位诊断价值。方法回顾性分析28例功能亢进异位甲状旁腺患者的手术、病理及影像资料。28例均行常规CT检查,其中25例先行双时相^99Tc^m-MIBI显像,对甲状腺外存在异常放射性浓聚灶患者,随即进行SPECT结合定位CT采集,经计算机处理得到二者融合图像,对放射性浓聚灶进行精确定位。以手术及病理检查结果为检查“金标准”,所有患者均按4个甲状旁腺计算,经手术及病理检查证实的为阳性,其余判为阴性。CT检查与核医学显像结果的比较采用四格表,检验。结果手术中28例患者共摘除28个异位病灶,均为单发。病理检查结果均为腺瘤。28例患者常规CT检查共发现22个阳性病灶,其中真阳性17个,假阳性5个,另假阴性11个,真阴性79个;25例^99Tc^m-MIBISPECT结合定位CT显像发现阳性病灶23个,无假阳性,另假阴性2个,真阴性75个。常规CT检查与核医学显像对检出病理性甲状旁腺的灵敏度分别为61％（17／28）、92％（23／25）,特异性为94％（79／84）、100％（75／75）,准确性为86％（96／112）、98％（98／100）,阳性预测值为77％（17／22）、100％（23／23）,阴性预测值为88％（79／90）、97％（75／77）;两者间比较差异有统计学意义,灵敏度：χ^2=6．98,P〈0．01,特异性：χ^2=4．61,P〈0．05,准确性：χ^2=10．30,P〈0．01,阳性预测值：χ^2=5．88,P〈0．05,阴性预测值：χ^2=5．36,P〈0．05。结论^99Tc^m—MIBI SPECT结合定位CT显像对功能亢进异位甲状旁腺的定位诊断优于常规CT,但存在一定的假阴性。     

兔原代胸主动脉平滑肌细胞培养方法及不同浓度血清培养基对其增殖的研究

目的探讨体外分离培养兔原代胸主动脉平滑肌细胞（vascular smooth muscle cells, VSMCs）技术及在不同浓度血清培养基下生长情况。方法采用组织贴块法进行原代培养,分别用不同浓度血清培养基（10％、15％、20％）对原代VSMCs进行培养．胰酶消化法传代,用倒置显微镜对原代培养兔平滑肌细胞进行形态学观察并鉴定,MTT法测定增殖能力。结果体积分数20％血清的DMEM培养液培养的原代细胞生长出现明显对数期。培养5代的兔平滑肌细胞纯度达97％以上：镜下可见平滑肌细胞生长,免疫组化提示平滑肌细胞肌动蛋白阳性表达,细胞生长第4～5d内光密度值变化较明显。结论本法能有效提高兔动脉平滑肌细胞原代培养的成功率,为研究血管平滑肌细胞生物学行为提供了有效模型。     

MEBO对烧伤病人血管内皮细胞保护作用的体外实验研究

目的探讨MEBO对烧伤病人血管内皮细胞的保护作用及其机理。方法将烧伤血清加入M199培养液配成20％烧伤血清培养液(BSM)，加入培养融合的人脐静脉内皮细胞中，设立1、3、6、12h4个时间点，光镜下观察各时相点人脐静脉内皮细胞的形态学变化，MTT法测定细胞活力。结论MEBO能明显改善烧伤血清所致的血管内皮细胞形态学变化，维持血管内皮细胞的完整性和连续性，并能明显降低烧伤血清对血管内皮细胞活力的影响。     

同型半胱氨酸对血管内皮细胞表达和分泌TFPI的影响

目的 观察不同浓度的同型半胱氨酸(Hcy)对血管内皮细胞表达和分泌组织因子途径抑制物(TFPI)的影响。方法 传代培养ECV304细胞，随机给予7种不同浓度(0、25、50、100／μmol／L，1、5、10mmol／L)的Hcy，24h后，用四唑盐比色试验(MTT法)检测细胞活力；用生化分析仪检测细胞上层培养液中的LDH含量；用ELISA方法检测细胞上层培养液中游离TFPI的浓度和细胞总的TFPI含量。结果 Hcy的浓度增加到5mmol／L后，细胞活力开始下降，10mmol／L时可以导致细胞LDH漏出量增加。不同浓度的Hcy作用24h均可以使细胞培养液中的游离TFPI浓度增加，使细胞总的TFPI的A值显著增加，以50-μmol／L组最为显著。结论 生理浓度的Hcy不直接对内皮细胞造成影响，但可以促进TFPI的表达和分泌，这可能与高同型半胱氨酸血症患者的血浆TFPI水平增高有关。     

过氧化氢对体外关节软骨细胞损伤效应及丹参干预作用实验研究

目的：观察过氧化氢（H2O2）对体外培养关节软骨细胞的损伤效应及丹参（salvia miltiorrhiza，SM）的干预作用。方法：采用兔原代膝关节软骨细胞培养技术，将培养的软骨细胞随机分为正常组、损伤对照组（损伤组）和丹参组。损伤组用0．1mmol／L过氧化氢（终浓度）制造体外软骨细胞损伤模型，丹参组将不同浓度的丹参（终浓度0．01g／L、0．05g／L、0．25g／L）于过氧化氧损伤前30min加入，分别测定各组细胞活力（MTT法）及细胞凋亡的变化，测定培养液上清中乳酸脱氢酶（LDH）活性及丙二醛（MDA）含量（硫代巴比妥酸法）变化。结果：0．1mmo／L过氧化氢对体外关节软骨细胞有损伤作用，诱导细胞凋亡作用明显：丹参组细胞活性较损伤组显著升高，软骨细胞凋亡率明显下降，培养液上清LDH、MDA水平显著降低，丹参的保护作用呈浓度依赖性。结论：过氧化氢能诱导体外关节软骨细胞凋亡，丹参对过氧化氢造成的软骨细胞损伤具保护作用。     

自身免疫性肝炎与原发性胆汁性肝硬化重叠综合征的临床与病理学研究

目的 探讨自身免疫性肝炎与原发性胆汁性肝硬化重叠综合征（AIH-PBCOS）的临床病理学特征。方法 对17例临床资料完整、行肝穿刺检查的AIH-PBC0s病例进行临床资料、生化检查和血清自身抗体指标分析，并与117例自身免疫性肝炎和85例原发性胆汁性肝硬化作比较，采用HE染色、网状纤维和胶原纤维染色，结合CK19免疫组织化学染色，探讨其病理学特点，应用免疫组化方法观察肝组织内CD3、CD4、CD8、CD20、CD25、CD57和CD68阳性细胞数量、比例和分布状况。结果该组AIH-PBCOS病例占总的自身免疫性肝病（自身免疫性肝炎＋原发性胆汁性肝硬化）的8．4％，男女比例为1：8．5，平均发病年龄39．3岁，其中血清ANA与抗M2抗体双阳性病例占52．9％（9／17），所有病例血清AIT、AST、TBIL、ALP、3γ-Gto、IgG和IgM均较明显升高。病理学观察见汇管区与肝腺泡内以单个核细胞为主的较多炎细胞浸润，其中易见浆细胞的聚积性浸润。可见不同时期小胆管损伤或细胆管反应性增生并侵蚀肝界板。肝组织内CD^3＋、CD^4＋、CD^8＋、CD20^＋、CD25^＋、CD57^＋及CD68^＋细胞数增加，其中CD3^＋、CD8^＋及CD68^＋细胞比例偏高，尤以损伤小胆管及肝细胞周围为著。结论 中国自身免疫性肝病患者群中存在少数（本组病例8.4％）AIH-PBC OS，该重叠综合征具有自身免疫性肝炎与原发性胆汁性肝硬化双重病理特征性改变，细胞免疫为主的免疫性损伤可能是其主要的免疫病理损伤机制。     

血清浓度对TGF—β1刺激成纤维细胞增殖的影响

目的比较低血清浓度（0．4％）和正常血清浓度（10％）培养条件对TGF-β1刺激成纤维细胞增殖的影响。方法原代大鼠皮肤成纤维细胞分别采用0．4％和10％血清浓度培养，加TGF-β1刺激细胞后，分别用BrdU ELISA法检测细胞增殖情况，噻唑蓝（MTT）比色法制作细胞生长曲线。结果0．4％和10％血清浓度下，250pg／ml TGF-β1均促进成纤维细胞增殖（P〈0．01），并促使生长曲线的峰值提前和增加。而25ng／ml TGF-β1均抑制成纤维细胞增殖（P〈0．05），并导致生长曲线峰值的滞后和降低。结论血清浓度对大小剂量TGF-β1刺激成纤维细胞增殖变化无明显影响。     

Bile leakage during transjugular intrahepatic portosystemic shunt creation: in vitro effect of bile on growth and function of human umbilical vein endothelium

PURPOSE: To evaluate the effect of bile on growth and proliferation of human umbilical vein endothelium cultured in vitro, with a view toward clarifying the effect of bile leakage during transjugular intrahepatic portosystemic shunt creation. MATERIALS AND METHODS: This study was approved by the ethical review committee, and written informed consent was obtained from all mothers. Endothelial cells (ECs) were collected from human umbilical veins and cultured in vitro. After 24-48 hours in culture, ECs were distributed into groups supplemented with the following concentrations of bile in the culture medium: 0%, 5.0%, 10.0%, 15.0%, 20.0%, and 25.0%. The cells were harvested 5 days after supplementation with bile. The morphologic features, von Willebrand factor (vWF) level, tetrazolium salt (MTT) assay value of light absorption, total protein level, and nitric oxide synthase (NOS) activity of the ECs were evaluated. RESULTS: All explanted cells were identified as ECs by using the vWF test. Compared with ECs in the control group without bile, ECs in culture medium with a bile concentration of 5.0%, 10.0%, or 15.0% showed no marked morphologic changes, whereas ECs in culture medium with a bile concentration of 20.0% or 25.0% were reduced greatly in number and looked markedly immature. The MTT value of light absorption, total protein level, and vWF secretion were significantly decreased (P < .05 for all) in ECs in culture medium with 25.0% bile compared with these parameters in ECs in culture medium without bile, although these parameters did not significantly differ between the ECs in culture medium of 5.0% or 10.0% bile and the ECs in culture medium without bile. Compared with NOS activity in ECs when no bile was present in the culture medium, NOS activity in ECs was significantly decreased at all bile concentrations (P < .05). CONCLUSION: Low concentrations of bile do not markedly inhibit cell growth; the inhibiting effect of bile on ECs progresses with an increase in bile concentration.     

中性粒细胞和内皮细胞凋亡及相关因子改变在晚期创伤性脓毒症发病中的作用

目的探讨中性粒细胞及内皮细胞凋亡及相关细胞因子和凝血因子改变是否参与晚期创伤性脓毒症的发病。方法收集晚期创伤性脓毒症患者外周血,分离培养外周血单个核细胞(PBMC)及中性粒细胞,观察创伤性脓毒症患者中性粒细胞和内皮细胞凋亡情况,并检测PBMC培养上清白细胞介素(IL)-4、IL-10以及外周血组织因子(TF)、血管性血友病因子(vWF)的水平,比较晚期创伤性脓毒症组与对照组的差异。结果晚期创伤性脓毒症组中性粒细胞凋亡水平[(37±21)%]和循环内皮细胞凋亡[(774±211)个/ml]水平显著高于非脓毒症创伤组[(16±9)%,(92±72)个/ml]和正常对照组。晚期创伤性脓毒症组抗炎细胞因子(IL-4、IL-10)及凝血因子(TF、vwF)水平显著高于对照组。结论晚期创伤性脓毒症患者存在免疫功能抑制和凝血功能异常,这可能是晚期创伤性脓毒症的特征之一,并可能是晚期创伤性脓毒症多脏器功能障碍发生的重要机制。     

TIPS术中胆汁漏出：刺激平滑肌细胞增生?

目的经颈内静脉肝内门腔静脉分流术（ＴＩＰＳ）中胆道损伤并胆汁漏出，可能是引起ＴＩＰＳ术后支架内平滑肌细胞（ＳＭＣ）增生和狭窄的重要因素。本研究以离体ＳＭＣ培养和ＴＩＰＳ猪模型实验评价胆汁对ＳＭＣ的作用。材料与方法离体ＳＭＣ培养分为三组：Ⅰ组＝１．０％血清＋１．０％胆汁；Ⅱ组＝１０．０％血清＋１．０％胆汁；Ⅲ组＝１０．０％血清。细胞收获点分别为３、１０、１４天。动物实验组共用４５只猪建立ＴＩＰＳ模型，术后处死时间为１０～１６天。结果此前预试验结果：使用２．５％、５．０％、１０．０％胆汁的培养基，ＳＭＣ在３天内全部死亡。离体细胞培养（１．０％胆汁）实验组（Ⅰ、Ⅱ组）中的脱氧核糖核酸（ＤＮＡ）和总蛋白量明显较对照组（Ⅲ组）少（Ｐ＜０．０５），且随着培养时间的延长其差异增加。动物实验组：２８．８９％的标本证实有胆汁漏出。定量分析示胆汁漏组中的ＳＭＣ增殖量较无胆汁漏组少。组织学检查发现有新生胆管在支架内生长。结论２．５％～１０．０％胆汁杀死ＳＭＣ，１．０％胆汁可抑制ＳＭＣ生长。动物实验示胆汁漏出导致ＳＭＣ增生减少，但血栓形成增加，从而使支架闭塞率增高。     

苯那普利对动脉粥样硬化形成及循环内皮细胞与假血管血友病因子的影响作用

观察苯那普利对高胆固醇饲喂的家兔动脉粥样硬化形成及其对循环内皮细胞 (CEC)、假血管血友病因子(vWF)的影响。 2 4只新西兰雄性大白兔随机分成 3组 ,对照组饲喂普通饲料 ,动脉粥样硬化组饲喂 1 %胆固醇饲料 ,苯那普利组饲喂 1 %胆固醇及苯那普利5mg/d。实验前、实验后 5周、实验后 1 0周分别抽血测血脂、vWF、CEC计数。第 1 0周末处死大白兔 ,计算主动脉斑块面积。结果显示 ,苯那普利治疗组与动脉粥样硬化组血脂水平无明显变化 ,但动脉粥样硬化斑块面积却明显减少(P <0 0 1 ) ,其血浆vWF浓度亦明显降低(P <0 0 1 )。提示苯那普利具有抗动脉粥样硬化作用 ,其机制可能与保护内皮功能有关     

A method for reducing radiation dose in cerebral CT perfusion study with variable scan schedule

PURPOSE: To propose a method for reducing the radiation dose in cerebral CT perfusion studies by using a variable scan schedule. MATERIALS AND METHODS: Original images were obtained with a multi detector-row CT (MDCT) scanner using the following CT perfusion protocol: continuous scans of 1 sec/rotation x 60 sec, four 5-mm-thick contiguous slices. The original images were thinned-out using combinations of various numbers of former continuous images (10, 15, 20, 25, and 30), and the later skipped images with various scan intervals (2, 5, 10, 15 and 20 sec). The thinned-out images were interpolated by linear interpolation. In five patients with cerebrovascular disease, we generated functional images of cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) from both original and interpolated data. The correlation coefficients (CC) for these parameters between the original and interpolated images were evaluated. RESULTS: The CC decreased with dose reduction. To keep the correlation coefficients greater than 0.9, the estimated dose was reduced to 33.3% on CBF with a set of 10 continuous images and scan interval of 5 sec, to 20.0% on CBV with a set of 10 continuous images and scan interval of 20 sec, and to 58.3% on MTT with a set of 10 continuous images and scan interval of 2 sec. CONCLUSION: The variable scan schedule method would be useful to reduce radiation dose while maintaining the accuracy of CT perfusion (CTP) parameters.     

体外循环下冠脉搭桥术后内皮功能异常和脂质氧化状态变化

目的评价体外循环对冠脉搭桥患者术后内皮功能和脂质氧化状态的影响。方法35例需要进行冠脉搭桥(CABG)手术的患者(女性5例,男性30例,年龄59.5±8.6岁)和20例正常对照者(女性5例,男性15例,年龄49.5±7.3岁)收入本研究。在术前、术后3天和术后7天采集血样。血浆vonWillebrand因子(vWF)和氧化低密度脂蛋白(oxidizedlowdensitylipid,OxLDL)水平分别代表了内皮功能异常和脂质氧化情况,均采用ELISA试剂盒检测。结果冠脉搭桥患者术前vWF和OxLDL水平较正常对照显著升高,分别为139.60%±34.39%vs82.79%±13.89%和63.7±18.9U/mlvs25.4±15.2U/ml。术后3天和7天,冠脉搭桥患者的vWF水平与术前相比显著升高,分别为194.30%±37.74%;181.07%±31.05%vs139.60%±34.39%(P<0.0001),OxLDL水平也显著升高,分别为79.3±26.7U/ml;72.4±23.1U/mlvs63.7±18.9U/ml(P<0.01)。结论与正常人群相比,CABG患者的内皮显著受损,脂质氧化水平显著升高。体外循环下CABG手术会加剧这些改变,提示术后患者更容易发生急性冠脉事件。     

阿魏酸钠对ox-LDL诱导血管内皮细胞凋亡的影响

目的观察阿魏酸钠(SF)对氧化修饰的低密度脂蛋白(ox-LDL)诱导血管内皮细胞凋亡的保护作用。方法将体外培养的人脐静脉内皮细胞(HUVEC)分为5组,分别为对照组,ox-LDL(50mg/L)组,SF低浓度(5μmol/L)组,SF中浓度(10μmol/L)组及SF高浓度(20μmol/L)组。SF低、中、高浓度组在加入含相应浓度的SF培养1h后,加入终浓度为50mg/L的ox-LDL。采用MTT比色法确定SF的作用浓度。分别采用Hochest 33258细胞核荧光染色法(定性)和流式细胞仪(定量)检测SF对ox-LDL致内皮细胞凋亡的影响。结果一定浓度的SF能够抑制ox-LDL引起的HUVEC存活率降低,对HUVEC损伤具有拮抗作用,40μmol/L以下是SF拮抗细胞损伤的最佳浓度范围。Hochest33258染色后ox-LDL组细胞核显示较强蓝色荧光,可见核固缩、凋亡小体等典型的凋亡形态学特征;加入20μmol/L SF后,细胞核基本恢复其正常形态。流式细胞术结果显示,加入低、中、高浓度的SF后,其细胞凋亡率分别为25.21%±4.07%、12.45%±2.65%、10.85%±1.23%,与ox-LDL组(31.14%±4.29%)比较均明显降低(P<0.05),且存在量效关系。结论 SF具有拮抗ox-LDL诱导的HUVEC损伤,减少血管内皮细胞凋亡的作用。     

Mononuclear cell adhesion and cell adhesion molecule liberation after X-irradiation of activated endothelial cells in vitro

Purpose : Increased expression of cell adhesion molecules on endothelial cells is an important early event in inflammation. Low-dose radiotherapy is very effective anti-inflammatory treatment. The hypothesis that it may act by modulation of cell adhesion molecule expression in activated endothelial cells and the subsequent adhesion of mononuclear cells onto the activated endothelial cells was tested. Materials and methods : EA.hy.926 endothelial cells were irradiated with 0.3-10 Gy X-rays at different times before or after stimulation with TNFα. ICAM-1 or E-selectin expression was measured by ELISA and FACS. Isolated peripheral blood mononuclear cells were incubated with an activated and irradiated confluent monolayer of endothelial cells 4 h, 12 h or 24 h after stimulation, and adhesion was determined in dynamic and static adhesion assays. Results : In the static adhesion assay, where integrin-mediated adhesion dominates, radiation doses of 0.3-0.6 Gy reduced the adhesion of mononuclear cells onto EA.hy.926-EC in vitro by 25-40% and 15-25% of the control level 4 h and 24 h after stimulation, respectively, but increased adhesion 12 h after stimulation. In the dynamic adhesion assay, where selectin-mediated adhesion dominates, radiation doses of 0.3-0.6 Gy reduced the adhesion events by 40-50% and 30-40% of the control level 4 h and 24 h after stimulation, respectively, and again increased adhesion 12h after stimulation. X-ray doses of ≤5 Gy did not induce ICAM-1 expression, or modulate TNF α -induced ICAM-1 expression. E-selectin expression was, however, increased in a dose-dependent way 6 h after irradiation. In contrast, X-irradiation 2-5 h before stimulation decreased the characteristic transient expression of E-selectin after TNF α stimulation. Conclusions : Modulation of E-selectin liberation on activated endothelial cells may be one mechanism to decrease leukocyte adhesion after low-dose irradiation in vitro, and could be involved in the therapeutic action of anti-inflammatory radiotherapy.     

Mononuclear cell adhesion and cell adhesion molecule liberation after X-irradiation of activated endothelial cells in vitro

PURPOSE: Increased expression of cell adhesion molecules on endothelial cells is an important early event in inflammation. Low-dose radiotherapy is very effective anti-inflammatory treatment. The hypothesis that it may act by modulation of cell adhesion molecule expression in activated endothelial cells and the subsequent adhesion of mononuclear cells onto the activated endothelial cells was tested. MATERIALS AND METHODS: EA.hy.926 endothelial cells were irradiated with 0.3-10 Gy X-rays at different times before or after stimulation with TNFalpha. ICAM-1 or E-selectin expression was measured by ELISA and FACS. Isolated peripheral blood mononuclear cells were incubated with an activated and irradiated confluent monolayer of endothelial cells 4 h, 12 h or 24 h after stimulation, and adhesion was determined in dynamic and static adhesion assays. RESULTS: In the static adhesion assay, where integrin-mediated adhesion dominates, radiation doses of 0.3-0.6 Gy reduced the adhesion of mononuclear cells onto EA.hy.926-EC in vitro by 25-40% and 15-25% of the control level 4 h and 24 h after stimulation, respectively, but increased adhesion 12 h after stimulation. In the dynamic adhesion assay, where selectin-mediated adhesion dominates, radiation doses of 0.3-0.6 Gy reduced the adhesion events by 40-50% and 30-40% of the control level 4 h and 24 h after stimulation, respectively, and again increased adhesion 12h after stimulation. X-ray doses of < or =5 Gy did not induce ICAM-1 expression, or modulate TNFalpha-induced ICAM-1 expression. E-selectin expression was, however, increased in a dose-dependent way 6 h after irradiation. In contrast, X-irradiation 2-5 h before stimulation decreased the characteristic transient expression of E-selectin after TNFalpha stimulation. CONCLUSIONS: Modulation of E-selectin liberation on activated endothelial cells may be one mechanism to decrease leukocyte adhesion after low-dose irradiation in vitro, and could be involved in the therapeutic action of anti-inflammatory radiotherapy.